Vaccination against many infectious diseases has provided enormous benefit in developed countries, leading to the virtual eradication of diseases such as polio, measles, smallpox, and others. However, efforts to create long-lasting vaccines against some viral infections, like Influenza and HIV, have not been successful to date because:
A) Viruses like HIV and Influenza undergo antigenic variation to evade previous immune responses.
B) Viruses like HIV and Influenza spread too rapidly in the population for a vaccine to be effective.
C) Viruses like HIV and Influenza have RNA, rather than DNA genomes, and are resistant to current vaccine strategies.
D) Viruses like HIV and Influenza infect via mucosal surfaces, a route that is not well protected by current vaccine strategies.
E) Viruses like HIV and Influenza are transmitted vertically (from mother to child) during fetal development, so babies are infected before they can be vaccinated.

Question

Quizplus · Accepted Answer

Viruses like HIV and influenza undergo rapid antigenic variation. Therefore, an immune response against one strain of the virus will not usually protect individuals from infection with a variant strain. Therefore, much of the current effort toward developing vaccines against these viruses aims at targeting highly conserved regions of the virus, where an immune response would be broadly reactive to many viral variants.

Vaccination Against Many Infectious Diseases Has Provided Enormous Benefit in Developed